Rolling platformer

Platformers in which the player controls a ball or other sort of sphere. Players must navigate the ball through various courses with obstacles that attempt to prevent the ball from reaching its goal. Common elements include unprotected edges that players can fall off of, moving obstacles and shifting stages, powerups that allow the ball to perform different actions, and uphill/downhill grades that slow down/speed up the player's ball. Games include Marble Madness, Super Monkey Ball, Rock of Ages, Marble Blast and Katamari Damacy.